SystemIntPtr

System.IntPtr is a value type in the .NET framework that represents a platform-specific pointer or handle. It is used in managed code to hold addresses returned by unmanaged code, to pass pointers to native functions via P/Invoke, or to represent native handles in interop scenarios. The size of an IntPtr matches the pointer size of the executing process: 4 bytes on 32-bit systems and 8 bytes on 64-bit systems, accessible via IntPtr.Size.

As a struct, IntPtr is immutable and copied by value. It provides a static field Zero to represent a null pointer or handle. It also offers pointer arithmetic support through static methods Add(IntPtr, int) and Subtract(IntPtr, int). For interop and low-level work, IntPtr can be converted to and from integral types: explicit conversions to int and long, and ToInt32/ToInt64 instance methods to obtain numeric representations. In unsafe code, ToPointer converts an IntPtr to a native void* pointer. IntPtr supports standard value-type semantics, including equality comparisons and hashing.

Common usage patterns include storing handles returned by unmanaged APIs, such as device, window, or module handles, or addresses allocated in unmanaged memory. It is widely used in marshaling scenarios and in code that interoperates with native libraries. While IntPtr provides flexibility for pointer manipulation, best practices recommend using SafeHandle-derived types or other managed abstractions when possible to manage native resources safely and avoid leaks or unsafe errors.

See also: pointer types, unsafe code, P/Invoke, SafeHandle, Marshal class.